1-methyl estratrienes



United States PatentO 2,791,592 l-METHYL ESTRATRIENES Carl Djerassi, George Rosenkranz, Stephen Kaufmann, John Pataki, and Jesus Romo, Mexico City, Mexico, assignors to Syntex, S. A., Mexico City, Mexico, a cor poration of Mexico No Drawing. Original application March 31,1950, Se-

rial No. 153,296, new Patent No." 2,671,092, dated March 2, I954. Divided and this-application February 17, 1954, Serial No. 413,952

8 Claims. c1. 260-'-39'7.4

The present invention relates to cyclopentanoperhydrophenanthrene compounds. More particularly the present invention relates to novel estrogens and th'epr o duction thereof and especially l-methyl estrogens.

it has been previously set forth in the prior literature, as for example Inhoifen, Angew. Chem, vol; 59, p; 207, 1947, that the 1',4-diene-3-ones of the steroid series-readily undergo'aromatization' of ring A with'a concomitant migration of the angular methylgroup to yield so c'alled l-methyl phenols, as for example l-methyl estradiol, 1- methyl estrone, etc. These compounds were insoluble in alkali and devoid of estrogenic activity. 7

In accordance with the present invention various cornpounds have been prepared probably possessing the 1- methyl configuration and having very substantial estro-' genie activity. Further, in contrast to the previously disclosed compounds the new compounds are soluble in alkali, have difierent melting points and other repe cities, and upon admixture with the previously known compounds have clearly demonstrated their difference as by depression of the melting points.

In application Serial No. 152,498, filed March 28, 1950, a novel process for the production of estrogens and intermediates is disclosed. Among the estrogen intermediates disclosed in'this application are the novel A '-3 ketosteroids. In particular, application Serial No. 152,498 discloses n -ii ketosteroidswhich may be exemplified by the following formula:

CHa CH3 wherein A may be C=OorCI-I -OR-andR may be=hydrogen, a'l'ower alkyl gronp, as for exaniple'rnethylor -eth ylor an aromatic groupsuchas'benzyl'bi' a'residue of a lower fatty acid or an aromatic acid, as for example acetic acid, propionic acid or ben'zoic acid. It has been found in accordance with the present invention'tha't' Awe-rewaemids, and particularly compounds of the character described; upon treatment with a catalyst capable" of pro'motingthe dienonephenol rearrangement, as

for example acetic acid anhydride or propionic acid anhydride together with paratoluene sulfonie' acid will rearrange to produce novel l-methyl-A estrogenswhich It has further been found in accordance with the present invention that the l-methyl-A -estroge'ns could be dehydrogenated in the presence of a suitable catalyst to produce the novel l-methyl equilenin' and derivatives thereof.

The production of the novel l-methyl-Mestrogen compounds of the present invention may be exemplified by the following equation:

10 C H: G H;

ij heat acetic anhydrlde P--to1uene sultonic acid In the above equation A may represent the groups previously set forth; Rx represents the residue of acetic acid or in the event propionic anhydride is used the residue of propionic acid. B represents C=O and'Cl-I-OR and Ry may be a lower alkyl group, as for example methyl or ethyl or an aromatic group such as benzyl or the residue of a lower fatty acid or an aromatic acid as for example acetic acid, propionic acid or benzoic acid. D'represents C=O or CH-OH.

In practicing the dienone phenol rearrangement above 40 set forth a mixture of trienone with paratoluene sulfonic acid and the acetic or propionic anliydride could be heated on a steam bath for a suitabIe-peribd of time, as for example five hours. The resultant solution was then cooled and hydrolyzed by agitation with water and the crystalline product thus precipitated was filtered, dried and recrystallized from asuitable solvent, as for example an alcohol such as methanol. The products could' be then further recrystallized from similar organic solvents for purification. The reaction proceeded both with the esters of the A -3-ketosteroids and also with the free compounds, i. e. those compounds wherein A is CH-'-OH, since those compounds were esterified under the'conditions of the reaction; For example-the product of the dienone phenol rearrangement of A androstatrien-3,17-dione using acetic anhydride was imethyl-n -dehydroestrone acetate and the product of the dienone phenol rearrangement of both A -androsta; trien-17-ol-3-one and its 17-acetate, was 1-methyl-A dehydroestradiol-3,l7-diacetate. The esters thus produced' could then be converted to the free compounds as by saponification with an alcoholic solution of a suitable aikali metal hydroxide by refluxing the ester therewith. Sulfonic acid could bealso used as a catalyst in place of the toluene sulfonic'acid' for the rearrangement 5 of the alcohols and derivative compounds, i. e. where A was CH-OR, and in this'case the reaction was carried out at room temperature.

The 1-methyl-A -dehydroestrone compounds may also be reduced utilizing lithium aluminum hydride to the corresponding 1-niethyl-A -dehydroestradiolcompoundsi This reaction may be performed generally by'dissoli/in'g" the l-methyl-n -dehydroestrone acetate for" example in a catalytic hydrogenation RIO CHI Ha saponlflmtion R.o H0

where Rx, B and D indicate the same groups previously set forth.

The hydrogenation reaction above set forth preferably takes place in the presence of a suitable catalyst such as palladium-on-charcoal or other suitable hydrogenation catalyst. For example, when a solution of I-methyI-A dehydroestrone acetate in ethyl acetate in the presence of a 10% palladium-on-charcoal catalyst was shaken in an atmosphere of hydrogen for approximately two hours or until the hydrogen take-up corresponded to 1 mol, l-methyl estrone acetate was produced. The l-methyl estrone acetate could then be saponified to produce 1- methyl estrone.

The 1methyl-M-dehydroestrogens can also be dehydrogenated to produce the corresponding novel 1-methyl equilenin compounds in accordance with the following reaction:

In the above reactions Rx, B and D represent the same groups as previously set forth.

In the above reaction the preferred dehydrogenating agent is selenium dioxide. However, other common dehydrogenating agents, such as palladized charcoal, other precious metal catalysts, chloranil and the like may be used. In general the 1methyl-A -dehydroestrogen is dissolved in a suitable solvent such as acetic acid or di oxane and refluxed for a short period of time with the catalyst under an atmosphere of nitrogen. The reaction mixture is then filtered to remove the selenium and the filtrate diluted with water. The resultant product is then filtered and recrystallized from a suitable solvent, such as methanol. The esters produced may then be saponified as previously set forth.

4 The following specific examples serve to illustrate the present invention but are not intended to limit the same:

Example I A mixture of 15.5 g. of A androstratrien-3,l7-dione, 3.90 g. of p.-toluenesulfonic acid and 600 cc. of acetic anhydride was heated for five hours on a steam bath. The cooled solution was hydrolyzed by swirling with water, the crystaline produce was filtered, dried and recrystalized from methanol; yield, 12.85 g. (72%), melting point 147-149 C. Further recrystallization from the same solvent gave pure 1rnethyl-M-dehydroestrone acetate with a melting point of 152-153 C. [061 94 (dioxane); ultra-violet maxima at 222 mu (log E 4.44) and 264 mu (log E 3.93).

Analysis-Calculated for CZHMOBZ C, 77.75; H, 7.46. Found: C, 78.09; H, 7.53.

Example ll Saponification of the acetate of Example I was accomplished in 97% yield by refluxing with 2% methanolic sodium hydroxide solution for one hour. Two recrystallizations from methanol gave l-methyl-u -dehydroestrone with a melting point of 250252 C. lul 87.7 (chloroform), -76.8 (dioxane); ultra-violet maxima at 228 mu (log E 4.49), 268 mu (log E 3.90) and 306 mu (log E 3.28).

Example III A mixture of 2.7 g. of A -androstatrien-l7-ol-3-one 17-acetate, 100 cc. of acetic anhydride and 1 g. of p-toluene sulfonic acid was subjected to the same procedure as in Example I. 2.89 g. (95%) of l-methyl- A -dehydroestradiol-3,17-diacetate was produced with a melting point of -113 C. Recrystallization from hexane gave in 71% yield the purified compound with a melting point of 116-1 17 C. hal l49; ultra-violet maxima at 222 mu (log E 4.46) and 264 mu (log E 3.96).

Analysis.Calculated for C23H2804Z C, 74.97, H, 7.65. Found: C, 74.76, H, 7.38.

This same rearrangement was also effected utilizing the free 17 hydroxy compound which was acetylated under the conditions of the rearrangement to produce the same product. The same reaction was also carried out utilizing 10% by weight of sulfuric acid as the catalyst instead of the p.-toluene sulfonic acid. When sulfuric acid was used as the catalyst, the reaction was preferably carried at room temperature.

Example IV Saponlfication of the diacetate of Example III by refluxing with 2% methanolic sodium hydroxide solution similarly to Example II produced in substantially quantitative yield 1methyl-M-dehydroestradiol having a melting point of 132 C. This melting point was unchanged after several recrystallizations from either hexane acetone or dilute methanol, MI -124 (chloroform), l34 dioxane; ultra-violet maxima at 226 mu (log E 4.57) and 266 mu (log E 3.95).

Analysis.-Calculated for Ciel-12402: C, 80.24, H. 8.50. Found: C, 80.48, H, 8.50.

The phenol produced was readily solublein 2 N aqueous sodium hydroxide and was benzoylated by the Schotten- Baumann method to produce 1methyl-M-dehydroestradiol 3-monobenzoate having a melting point of 146-1475 C. after recrystalization from hexane-acetone, [al -123.

Analysis-Calculated for CzeHaaOs: C, 80.42, H, 727. Found: C, 80.35, H, 7.19.

Example V A solution of 2 g. of l-methyl-A -dehydroestrone acetate of Example I in 600 cc. of dry ether was refluxed with 1 g. of lithium aluminum hydride for thirty minutes. After the usual work-up, there was obtained 1.54 g. (88%) of l-methyl-M-dehydroestradiol having a melting point of 129-132 C., which gave no depression on admixture with the sample prepared according to Example IV and possessed the same rotation and spectrum.

Example VI A solution of 4 g. of 1-methyl-A dehydroestrone acetate having a melting point of 147-149 C. of Example I in 60 cc. of ethyl acetate was shaken in the presence of hydrogen with 800 mg. of 10% palladium-on-charcoal catalyst for two hours, at which time the hydrogen uptake corresponded to one mol. After filtration, evaporation and recrystallization from methanol, 3.5 g. (87%) of l-methylestrone acetate was obtained having a melting point of 157.5-158.5 C. [a] +240 (chloroform),+2l9 (dioxane; ultra-violet maximum at 268 mu (log E 2.52) and minimum at 252 mu (log E 2.31). It is to be noted that the so-called l-methylestrone described in the literature did not form a crystalline acetate.

Analysis.-Calculated for C21H2s03: C, 77.26; H, 8.02. Found: C, 77.14; H, 8.20.

Example VII Alkaline saponification of the l-methylestrone acetate of Example VI in accordance with the procedure of Example II lead in quantitative yield after recrystallization from methanol to l-methylestrone, having a melting point of 250-252 C. [u] +257 (chloroform),+246 (dioxane); ultra-violet maximum at 282 mu (log E 3.26) and minimum at 250 mu (log E 2.51). The so-called 1- methylestrone, described in the literature, had a melting point of 249-251" [a] +27l.6 and a mixture of the two specimens melted at 2l2223 C. In contrast to the latter substance, l-methylestrone of the present invention dissolved on warming in aqueous alkali and exhibited approximately one-half the estrogenic potency of estrone in rats.

Analysis.-Calculated for C19H2402: C, 80.24; H, 8.50. Found: C, 80.05; H, 8.50.

Example VIII Hydrogenation of the A -dehydro diacetate of Example III in the manner described in Example VI, in ethyl acetate solution with palladium-on-charcoal catalyst (barium sulfate supported catalyst was equally satisfactory) aiforded 81% of shiny, prismatic blades (from methanol) of 1-methylestradiol-3,l7-diacetate with a melting point of 178180 C. [a] +111; ultra-violet maximum at 268 mu (log E 2.53) and minimum at 252 mu (log E 2.44). The so-called l-methylestradiol 3,17- diacetate described in the literature had a melting point of 138.5439".

Example IX l-methylestradiol, prepared either by saponification of its diacetate of Example VIII or by hydrogenation of 1- methyl-A -hydroestradiol of Example IV in accordance with the procedure of Example VI, was obtained from ether-hexane as a microcrystalline powder, which shrank at 95 C. and melted at 110-116 C. [a] +l46; ultra-violet maximum at 284 mu (log E 3.28) and minimum at 250 mu (log E 2.25). The physical constants of this alkali-soluble estrogenically potent phenol are in complete contrast to those reported for the so-called lmethylestradiol: insoluble in alkali, crystallizes readily, melting point 2355-2365 [a] +-l85 (dioxane).

Analysis-Calculated for CrsHzsOn: C, 79.67; H, 9.14. Found C, 79.87; H, 9.36.

Example X The 3,17-dipropionate of the l-methylestradiol of Example IX was isolated in nearly quantitative yield on heating l-methylestradiol for one hour with propionic anhydride and pyridine; colorless plates from methanol, having a melting point of 125.5-127 C. [a] -|10l.5; ultra-violet maximum at 268 mu (log E 2.58) and minimum at 254 mu (log E 2.45).

. 6 Analysis.-.Calculated for C25H3404! c, 75.34; 8.59. Found: C, 75.16; H, 8.63.

Example X I Example XII Alkaline saponification of the acetate of Example XI afforded l-methylequilenin, which after recrystallization from aqueous methanol had a melting point of 215- 217 C. [a] +138.5 (dioxane). The ultra-violet spectrum closely resembled that of equilenin.

Example XIII A mixture of 1 g. of 1-methy1-A -dehydroestradiol 3,17-diacetate, 0.15 g. of selenium dioxide and 15 cc. of glacial acetic acid was refluxed for fifteen minutes. After filtering, pouring into water and recrystallizing from hexaneacetone, colorless plates of l-methyl-17-dihydroequilenin 3,17-diacetate with a melting point of 136-137 C. [a] 16 (chloroform) was obtained. Saponification and recrystallization from aqueous methanol or hexane-acetone yielded l-methyl-17-dihydroequilenin- 17 3, having a melting point of 225227 C. [u] +33 (dioxane).

The last-mentioned compound could also be obtained by lithium aluminum hydride reduction of the 1-methyl equilenin acetate of Example XI.

The present application is a division of the application of'Djerassi, Rosenkranz, Kaufmann, Pataki and Romo, Serial No. 153,296, filed March 31, 1950, now Patent No. 2,671,092 granted March 2, 1954.

We claim:

1. A l-methyl-estrogen compound selected from the class consisting of l-methyl-estrone having a melting point of 250-252 C., l-methyl-estrone acetate having a melting point of 157.5158 C., l-methyl-estradiol having a melting point of -116 C., l-methyl-estradiol-3,17-diacetate having a melting point of 178 -180 C., and l-methyl-estradiol- 3,17- dipropionate having a melting point of 125.5 127 C., said compounds being alkali soluble, have estrogenic properties and are prepared by hydrogenation of the corresponding I-methyl-A dehydro compound.

2. A process for producing a l-methyl-estrone comprising hydrogcnating 1-methyl-A -dehydroestrone in the presence of a palladium catalyst until approximately 1 mol of hydrogen has been taken up.

3. A process for producing l-methyl-estradiol, comprising hydrogenating l-methyl-A -dehydroestradiol in the presence of a palladium catalyst until approximately 1 mol of hydrogen has been taken up.

4. A new alkali-soluble compound having estrogenic properties, consisting of l-methyl-estrone having a melting point of 250-252 C. and prepared by hydrogenation of the corresponding 1-methyl-A -dehydro compound.

5. A new estrogenic compound, consisting of l-methylestrone acetate having a melting point of 157.5-158.5 C. and prepared by hydrogenation of the corresponding I-methyl-A -dehydro compound.

6. A new alkali-soluble compound having estrogenic properties, consisting of l-methyl-estradiol having a melting point of 110-1l6 C. and prepared by hydrogenation of the corresponding l-methyl-A -dehydro compound,

7. A new estrogenic compound, consisting of l-methyl- ,7 estradiol-3,17-diacetate having a melting point of 178- w I y 7 References Cited in the file of this patent 180 C. and prepared by hydrogenation of the correspond- UNITED STATES PATENTS l-methyLM-dehydro compound.

t I r l 2 280 828 Inhofien Apr. 28 1942 8' g a 1 V 2 A new estro emc compound consisting of 1 methyl 5 OTHER REFERENCES estradiol-3,17-dipropionate having a melting point of v 125.5127 C. and prepared by hydrogenation of the cor- Inhofienl Angewandte Chem- 471-75 responding l-methyl-A -dehydro compound. Inhofien: Angewandte Chem. 59, 207-12 (1947).

Wilds at 211.: J. Am. Chem. Soc. 68, 2125-33 (1946). 

1. A 1-METHYL-ESTROGEN COMPOUND SELECTED FROM THE CLASS CONSISTING OF 1-METHYL-ESTRONE HAVING A MELTING POINT OF 250*-252*C., 1-METHYL-ESTRONE ACETATE HAVING A MELTING POINT OF 157.5*-158*C., 1-METHYL-ESTRADIOL HAVING A MELTING POINT OF 110*-116*C., 1-METHYL-ESTRADIOL-3,17-DIACETATE HAVING A MELTING POINT OF 178*-180* C., AND 1-METHYL-ESTRADIOL -3,17-DIPROPIONATE HAVING A MELTING POINT OF 125.5*-127*C., SAID COMPOUNDS BEING ALKALI SOUBLE, HAVE ESTROGENIC PROPERTIES AND ARE PREPARED BY HYDROGENATION OF THE CORRESPONDING 1-METHYL -$4DEHYDRO COMPOUND. 